Compressed-air drill



Oct. 9 1923.

G. P. GOMEZ coMPREssED AIR DRILL Filed April 17 1922 j 6 Sheets-Sheet 1 rm.. m,

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@vtue/oa l.. .HEI

Oct. 9 1923. 1,470,074

G. P. GOMEZ COMPRESSED AIR DRILL Filed April 17. 1922 6 Sheets-Sheet 5 I y N Nm); f' .www V 'N h Oct. $1923. 1,470,074 G. P. GOMEZ l COMPRESSED AIR DRILL Filed April 17, 1922 6 Sheets-Sheet 4 G. P. GOMEZ coMPREssED AIR DRILL Oct. 9, 1923.

" Filed April 17. 1922 6 Sheets-Sheet 5 ...E j. v

Oct. 9, 1923.` 1,470,074

G. P. GOMEZ COMPRES SED AIR DRILL Filed April 1v. 1922 'e sheets-sheet e limi?. 2b

l. k /y Patented Oct. 9, 1923.

narran srefres titane PAT sur oreillers..

` GINES PEREZ GOMEZ, OF MIAMI, LARIZONA.

coMr'REssED-Ara DRILL.

Appncation ined April 17, 1922. seriaiNo. 553,731.

To oZZ whom it may concern:

Be it known that l, GINES P. GOMEZ. a

subject ot the King ot' Spain, residing" at Miami. in the county ot Gila and State of Arizona. have invented certain new and- This invention relates to an improved` compressed air drill and one lobject ot the invention is to' provide a lcompressed air drill havingV an improved type ot hammer for striking the linner end ot a drill steel carried by the improved drill or un asvit may be termed, and to further provide an improved type ot chuck for carrying the drill steel, the chuck being rotatably mounted and provided with improved pawls engaging a ratchet sleeve mounted in the body portion otf the lgun and having;` threaded engagement with the reciprocating hammer so that as this hammer reciprocates the ratrhet sleeve will he oscillated and impart step-by-step rotary movement to the chuck.

Another object ot the invention is to so mount the lhammer in the body of the run that when desired it-may be permitted lto strike plug which closes'the rear endy of the body portion ofthe gun and thus a drill steel permitted of being easily removedl from a hole which has been drilled in a rock., the hammer' ordinarily not havingJ contact with the closure plug for the rearvend 'of gun and hav/ingr sliding` movement .in the interior oit the barrel of the gun Without striking the plugv when moving rearwardly.

Another object of the invention is to provide an improved type of valve for controllingl the passage of compressed airinto and out or the barrel ot the gun, the valve beine' actuated by the .enlarged inner end portion ot the hammer and the `valve servto control passage of air into the ei;- pansion chamber Vor" the barrel and further servinojto provide .a conduit through which a draftrair may pass to the exhaust port of the valve housing.

Another object of the invention is to VAso construct this valve housing and rocher valve that the valve housing may be removably connected with the barrel of the -gun, and the rocker valve mounted inthe housing and pivotally mounted intermediate itslengfth with `its'end vportions extending longitudinally: ot the valve housing and provided With lugsextending through openings into the expansion chamber o't the barrel and into position for engagement by the enlargedportion of the hammer as the hammer reciprocates. i

Another object of the invention is to so construct the ratchet sleeve that it may be easily put in place upon the hammer with one end portion Aextending beyond the barrel and intothe chuck for engagement bythe pawls of Ithe chuck, the sleeve and hammer being'` provided with co-operatin-grv rifle threads tor imparting oscilla-ting` movement tothe ratchet sleeve and the'paivls, of the chuck being sol constructed that the chuck and drill. steel carried thereby may be caused torotate in a desired direction and also prevented from rotating-if so desired.

Another object of the invention is to `provide an improved type of hood for the chuck and improved meansto retain the hood. in place, the securing means tor the hood con-y sisting of rods or bolt elements which extend uponlopposite sides of the barrel and carry the plugs for closing the rear endot the barrehas Well as carryingy the hood, the barrel being slidable upon the `rods 'so that thevbarrel may be moved to effecty strikingr of the closure plugfby the rear end of. the hammer when so desired.

rrnother object of the invention is to provide improved meansl for imparting` move# ment to the paivls and adjust the position of the paWls to cause. the chuc'lr tov rotate in a desired direction when the drill ris in use.

Another object of the invention is to so mount these pawls that they will be' normally held in position to turn the chuck in y one direction by spring controlled vcam elel ments having" stem portions Which efitendior engagement by a ring moved to engage the stems and move the cams against the action tive position and when moved lii'st moving the pawls to render all of the pawls inoperative and iurtlier movement of the completing adjustment to cause rotation oi the chuck in an opposite direction. l

Another object of the invention is to provide a drill of the character described which can be readily taken apart for cleaning and repairing when so desired and to further so construct it that when put together, it will be very e'fiicient inyoperation and not of the will be Figure 16 is a perspective view sleeve upon which the valve housing secured.

Figure 17 is a bottom plan view valve housing.

Figure 18 is a sectional view taken along theline 18-18 ot' Fig. 4.-

y Figure 19 is a sectional view taken along the line 19-19 of Fig. 4, or along the line 1919 or yFig. 20.

Figure. 2O is a longitudinal sectional view of the liable to readily get out of order or haveA through the valve housing` taken along the any parts easily broken.

Another object of the invention is. to provide improved means for holding ,the drill steel in engagement with the chuck and limit movement or' the steel away from the chuck when struck by the hammer thus preventing the drill from slipping out oithe chuck when in use and further permitting the means controlling movement of the drill to have engagement with a collar when the plug closing the rear of the barrel is struck by the hammer so that the drill may oe easily removed from a. hole which has been drilled in a rock.

This invention isY illustrated in the accompanying drawings. wherein:

Figure 1 is a top plan view et the im-A proved air drill.

Figure 2 is a side elevation ot the same.

Figure 3 is a longitudinal sectional view through the air drill taken along the line 3-3 of Fig. 2.

Figure 4 is a longitudinal sectional view taken along the line 4-4 of Fig. l.

Figure 5 is a transverse sectional view taken along the line 5 5 of 4.

Figure 6 is a sectional view taken along); the line 6--6 oi Fig. 4 with the ratchet mech anism adjusted for turning the drill steel in one direction during operation of the drill.

Figure 7 is a sectional view taken along the line 7 7 of Fig. 6.

Figure 8 is a view similar to Fig. 6 showing the ratchet mechanism adjusted to rotate the drill steel in an opposite direction.

Figurey 9 is a sectional view taken along the line 9-9 ot' Fig. 8. .i

Figure 10 is a perspective view ot onevot' the ratchet tube members together with the actuating plunger for the same.

Figure 1l is a sectional view taken aloiui` the line 11H11 of Fig. l.

F igure 12 is a perspective view of the cam collar forming part ot' the ratchet shifting mechanism.

Figure 18 is a perspective view ot' a ring moved by the collar oit Fig.

Figure 14 is a fragmentary.sectional. vieu1 showing the latch means for releasably holding the collar against turning.

Figure 15 is a perspective view of the valve housing for controlling` passage of compressed air through the air drill.

line 9.0-20 of Figs. 2 and' 4.

F igure 211s a perspective view of a rocker element mounted in the valve housing and forming a portion of the valve mechanism.

Figure 22 is a perspective view of this f rocker arm looking at the bottom and open side thereof.

Figurey 23 is a sectional b view taken along the 4line 23-23 of Fig. 19.

Figure 9.4 is a perspective view of a valve Y plug for controlling the outlet of the valve housing.

Figure 25 is a transverse sectional view taken along the line 25-25 of Fig. 1.

This improved compressed`air drill or gun as it may be called, is provided with a barrel 1 which is open at its forward and rear ends and. has its rear end closed by a cap or plug 2 vwhich fits into the rear end portion of the barrel 1 and is provided with a packing ring 3 so that leakage of compressed air around this closure plug will be prevented. A sleeve or filler 4 fits into the tforward end aortion ot' the barrel 1 and is provided with a packing ring 5 so that leakage oiy air around this sleeve will be prevented. The hammer 7 is provided with an enlarged rear end portion formino; a head 8 which is positioned in the expansionchamber of the barrel and serves as a piston element by means ot which reciprocating movement may be imparted to the hammer as will be hereinattcr brought out. This hammer 7 extends through the sleeve 4 and has its forward end portion provided with rifle threads 9 which iit into co-operating rifle grooves formed in a ratchet sleeve 10 which fits upon the forward end portion of the hammer 7 and within the enlarged forward end portion of thel passage through the center ot the sleeve 4. The head 8 ot the hammer is non-circular when viewed in end elevation and will be preferably six-sided as shown in Fig. 18 but may7 be provided with any number of side 'faces desired.l The interior of the barrel 1 between the portion which receives the plug 2 and a portion which receives the sleeve 4 corresponds in shape to the head 8 and it will thus be seen that although the hammer may slide longitudinally in the barrel. it cannot rotate therein. Therefore, when the hammer is reciprocating in the barrel and sleeve 4, the riling of the hammer and lll `nar/021074:

ratchet sleeve will cause this ratchet sleeveto have oscillating 1novement. Recesses 11`which 'provide ratchet teeth are formed about the end portions of the ratchet sleeve, one 'set ofl ratchet teeth being provided at each end of the ratchet sleeve so that when assembling the ratchet sleeve may be p ut in .placeV with either end innermost and thus always have Lthe out-er'end portion of the yratchet sleeve rprovided with the ratchet teeth.` -Side bars 12 which are rectangularin cross section vthroughout the greater portiony of `their length extend between the side arins 13and 14 of the barrel i 1 and are provided at their rear ends with reduced extensions ,l5 forming bolt elements whichextend through the:v perforated side ears 16 of the plug 2 and carry securing nuts 17. The forward endr portions 18 of these bars 12 are alsofreduced to provide pin extensions which extend through the perforated ears 19 of the sleeve 4, these ears 19 lbeing pro'vi'dedat opposite sides of a flange y2O formed adjacent the outer end ot' the sleeve; should hehnoted that the pins 1S are elongated so'nthat they may extend through the sleeves '21 formed at the sides ofxthe hood`22 and project upon opposite sides of theneck `portiona23 of this hood and carry bumper springs 24 and securing nuts 25 to holdvtvhe springsinplace. With the securing nuts 17 and 25 tightened the desiredamount, the parts will be assembled as shown in F ig. 3 and thebarrel will be permittedy oflongitudinal adjustment lso as to bring theplug 2 intoposition to be struck by the rear end of the hammer head 8 when it is desired to have a drill steel extracted froma hole which has 4been drilled. yUnder ordinary circiimstances;"the barrel will be positionedso that the hammer head will not stiikethe inner end of the plug 2 and will further be so positioned that sufficient space will be provided between the inner face of the plug and the hammer" so *that an air cushionv will be provided between the rear end ofvv the hammer' and the inner face of the plug. `A base 26 is provided for the barrel 1 so that when desired this air gun may be mounted uponaV suitable support. There has further been vprovided a handle 27 which extends upon opposite sides of thelbarrel and has each arm provided at its forward end with a socket 2.8 for receiving the shank portion of aclan'ip 29. Each of these clamps 29 is provided its lower end with a foot wliiclrextends Lbeneath the lower side arm 13 at its side of the barrel and each arm of the handle .27 is provided adjacent its free end with aA depending lug30, the lugs 30 fitting into recessesor seats 31 formed in the upper side arms 13and serving to hold the handle against longitudinalmovement when the 'securing nut-s, 29 are tightened. AFrom an inspection ofblig. `25,it will be readily seen that when the securing nuts 29 are tightened7 thel arms v13 will be brought into tight 'binding engagement with the side bars 12 vand the barrel will be securely held in a desired position and prevented from having longitudinal movement.

i .The chuck 32 rotatably fits in the hood ther so that'thedrill steel can be prevented from slipping out of the socket of the chuck. ln order to prevent the drill steel from slipping out ofthe chucln'there has been provided a hook 36 vhaving arms 37k which extend rearwardly from the drill-engaging portion of the hook and upon opposite. sides,

of the neck 23 of the hood. .Pivot pins 3S extend inwardly from the arms 37 and rfit into grooves 39 which are cut in the thickened side portions 40 of vthe neck 23: Springs -11 tit upon pin extensions 42 of the arms 37 and engage the end. face of the hood at the inner end of the neck 23 to provide means for yieldably `holding the steel-engaging hook against pivotal movement. It willjbe further noted that abutment screws L13 are provided to limit the tilting of the hook one direction and' prevent the hook from tilting to a position which will permit removal of thesprings and movement ofthe hook to bring the side pins 33 out r of the seats 39. lith the hook swung to the operative position shown in Figs. 1 and 2` vthe hook will engage the drill steel and through engagement with the shoulder 35 will serve to prevent 4the drill steel from becoming disconnected from the socket `of the chuck. When however it is desired to remove the drill steel, it is siinply necessary to swingfthe hook to an inoperative position'where it will be out of engagement with the drill steel and vpermit ready-removal of the same. lVhen the barrel 1 has been adjusted to bring the plug into position to be struck by the hammer when the hammer moves rearwardly. the plug. side bars.Y and hood will be drawn rearwardly andV since the hook will engage the shoulder 35. the drill steel will be extracted from a hole which has been drilled in a rock.

Then drilling` it .is necessary to turn the rio drill steel forja portion of a rotation before each blow is received and in order to do so,

the chuck which carries the drill steel *hasl been provided with pawlsffor engaging the ratchet teeth of the ratchetsleeve '10. v.The

lip portion of the pawls are arranged in sets and each set includes a pawl 44 for imparting rotary movement to the chuck and drill steel in a vlefthand'direction and a pawl 45 for imparting rotary movement in a right-hand direction. Each pawl is provided with a stem portion in the form of a pin 46 which fits into one of the sockets 47 of the chuck and is further provided with a lip or tongue extension 48 which is vapproximately one-half the depth of the toothed portion of the pawl as shown in 10. 1t should be noted that the lip portion 48 of the pawl 44 extends from the lower end portion of its pawl whereas the pawl 45 will extend from the upper portion of the toothed portion of its pawl. Plungers 49 are slidably mounted in sockets which are similar to the sockets which receive the stems of the pawls and these plungers which are positioned between the pawls 44 and 45 carry cross heads 50 which extend upon opposite sides of the plungers and are adapted to engage the lip extensions of the pawls. It should be notedv that the cross head 50 has its extended end portion provided with upper and lowerbevel faces so that movement can be imparted to the pawls when the plungers are moved. By having the end portions of the cross heads 50 provided with beveled upper and lower portions cams will be provided to cooperate with the beveled inner faces of the lips 48 and serve to rock the pawls to bring the ratchet engaging teeth of the pawls 44 out of an operative position when the plungers are moved in one direction and when moved in the opposite direction bring the ratchet-engaging teeth of the pawls 45 out of engagement with the ratchet teeth of the sleeve. 1t should be noted that when the plungers are only moved for a portion of their movement, both of the pawls will be held with their teeth out of engagement with the ratchet sleeve. In order to normally hold the pawls in position with their teeth extending for engaging the teeth of the ratchet sleeve.- there has been provided springs each having a bolt portion 51 which ts into a socket of the chuck and arms 52 which extend beneath and engage the teeth of the pawls. The pawls will therefore be normally held in the operative position and may be selectively held out of an operative position by proper adjustment of the, plungers. 1n order to hold the pawls and plungers in place. there has been provided a retainer' ring 53 which serves to limit outward movement of the pawls and plunge-rs and is held in place by flared end portions 54 which fit between the portions of the chuck carrying the pawls and plungers. A spring 55 is provided upon the inner end portion of each of the plungers beneath the cross head 50 so that the plungers will be normally held in the extended position shown in Fig. 9'

with the pawls 44 in the operative position as shown in Fig. 8. In order to press upon the extended ends of the plungers and move them inwardly against the action of the f springs 55 there has been provided a ring 56 which lits upon the neck extension 57 of the sleeve 4 and is provided with pins 58 which pass through openings formed in the collar 2O and engage the cam surfaces 59 of the ring 60. 1t will be readily seen that when this ring 60 is turned by means of the side extensions 61, the action of the cam surfaces 59 against the pins 58 will cause the ring or disk 56 to be moved and press the plungers inwardly against the action of the springs 55. When the ring is turned in an opposite direction, the springs will force the plungers outwardly and the pins 58 will thus be at all times held in engagement with the cam surfaces 59. This ring 50 is cut away at opposite sides as shown at 62 so that shoulders will be provided to engage the side bars 12 and limit rotation of the ring and clips 62 are carried by the ring and fit into grooves 63 formed in the collar 2O so that the ring will. be held against movement longitudinally of the sleeve 4 and prevented from moving out of the proper position when the barrel is shifted rearwardly. A friction ball 64 is mounted in a socket formed in the ring 50 beneath the side arms 61 and engaged by a spring 65 so that the collar may be turned but will be releasably held in an adjusted position due to the ball 64 being pressed into seats 66 formed in the sleeve 4. 1t will thus be seen thatv a very efficient means has been provided for adjusting the pawls to cause the chuck to receive a step by step movement in either a right-hand or a left-hand direction and further that the structure is so arranged that rotation of the chuck may be entirely prevented if so desired.

This drill is to be operated by compressed air which will be fed from a suitable source of 'supply and will enter a valve housing 67 through an inlet port 68.l This valve housing is secured upon a seat 69 formed upon the upperv portion of the barrel 1 and is secured by removable fasteners 70. The chamber 71 within the housing is open through the underface thereof and has its end portions communicating with the inlet ports 7,2 of the expansion chamber forming portion of the cylinder. This housing has its chamber 71 further provided with side ports 73 which communi- {cate withthe chamber 71 through the side walls thereof as shown in Figs. 15 and 20 and register with the exhaust ports 74 of the expansion chamber. A rocker valve 75 which is open at one side extends longitudinally in the valve housing and is provided with a side arm 76 which forms a bearing sleeve to receive the pivot pin 76 carried by thev valve housing. This rocker leo valve 7 5`is mounted inthe chamberv7l yof to bring its air passage 8O into. and out ofy position to register with the port 77. This plug valve is provided with an annular groove 8l which receives the spring pressed latch pin 82 so that the latch pin may serve to hold the plug valve against longitudinal movement. From an inspection of Fig. 20, it will be readily seen that when the rocker valve is in the position shown in Fig. 4,

air from the inlet port 68 may enter the :chamber 71 and pass through the ports 72 and through ports 7.3 and 74 into the expansion chamber to act upon the hammer and move it outwardly into striking engagement with the inner endlof the drill steel. As the hammer is moving outwardly, air in the opposite end portion of the expansion chamber will be forced through the ports 74 at this end and this exhausting air will pass upwardly through the ports 73 and side ports 74 into the interior of the hollow rocker shaftthrough which it will pass to the exhaust port 77. In order to 4impart movement to the rocker permit of its `being moved to into the proper a end of the chamber and permit air to admit L air expansion pass out of the oppositey end thereof, there has been providedlugs 83 `and 84 which are curved somewhat as shown 1n Fig. 22 and are positioned to lit into the openings 72..4

These lugs 83 and 84 extend into the valve housing so that as the hammer moves, the beveled portions 85 of the hammer head 8 will strike these and impart rocking movement to the valve. It` should `be further noted that these lugs serve to close the openings 72 and thuscause the exhausting air to pass -through the exhaust ports 74 and 73. If desired the housing can be provided with a port in one corner which receives a valve-controlled coupling 86, the coupling 86 being preferably constructed as shown in Fig. 2O and provided so that a pipe may be connected with this coupling and air led to an air control. feed for the drill. coupling, the valve which may be forcedinwardly to an open position will close and escapeof `air through thatfport willbe prevented. i

During operation of thedrill, itis desired to supply water to the bottom of the hole which is being drilled .so that dust can beprevented and the pointy of the drill steel prevented from being overheated.

valve and lVhen the pipe is removed from the i There has `therefore been provided a water pipe 87 which passes through the hammer and has its lforward end portion insertible into awater passage which is formedlongitudinally in the drill steel. This pipe 87 passes Vthrough a tube `88 which y passes through the plug 2 and into the rear end portionof the hammer, the opening in the hammer which receives the pipe 87 being enlarged to permit @the hammer lto` slide freely upon vthis tube 88. Vithin the pocket 89 which is formed in the plug 2, the tube 88 is ,provided with a head `or collar :90 and the pipe y87 is alsoprovided with a head or collar 9,1.which is held in closecontact with the, head "90 by means of an internally and externally threaded sleeve 92 which is Ascrewed into the threaded Aouter portion of thisl pocket 89. receives water from a suitable source of Isupply is provided with an; enlarged end portion engaged by a packing lgland 94 which .is screwed into the sleeve 92. It will thus be seen that when the gland 94 isl screwed tightly into place, water from the a source ofcompressed air 'supply and thisl compressed `air inthe chamber 67 of the valve housing will pass through the port 74 at one end thereof and move thehammer' longitudinally with thehea-d 8 of the hammer acting as a piston. As the hammer moves longitudinally of the barrel,'the air in front of the head isV driven out through the exhaust port at that end of the eXpansion chamber and passes throughthe vrocker valve and out through the exhaustI port of the valve housing. Uponreaching the end portion of the expansion chamber, the head of the hammer will strike the lug which projects into the expansionwchamber,thus rocking the rocker valve andv moving itxto reverse vits position thus closing the inlet port at one end and opening the inlet port at the end through which the air previously was exhausted. The air will now pass into the expansion chamber and willmove the hammer in a reverse directionv and the air will exhaust through the opposite end portion of the rockervalve. thus be reciprocated longitudinally and will act of itself to adjust the rocker valve` to The feed pipe 93 whichy The `hammer will f pipe 93 canpass through the pipe or tubeL move the rocker valveto the desired posi- -f will prevent excessive noise and prevent breakage when the hammer is stopped in its Vforward movement towards the sleeve l. As this hammer reciprocates, the rille threads will cause the ratchet sleeve l() to oscillate and with the collar or ring 60 set in the proper position, the chuck will receive a step-by-step rotary movement. The chuck will thus be rotated a portion of a revolution each time the hammer moves to strike the inner end ot the drill steel and therefore the hole drilled in the rock will be properly drilled without danger of the drill steel being wedged in the hole being drilled. The hook 36 serves to support and `guide the drill steel and further serves to prevent the drill steel from moving entirely out of the socket portion of the chuck. In withdrawing the drillpsteel from the hole which has been drilled, it is simply necessary to grasp the handle 27 and draw the gun away from the rock in which the hole is being drilled. The hook 36 will engage the shoulder 35 and the drill steel can be easily withdrawn.' The drill steel can be lett in place if desired or the hook can be swung' to one side so that it will not engage the reduced portion of the steel thus releasing the drill steel and permitting of its removal from the socket portion of the chuck. It when attempting to withdraw the steel from the hole which has been drilled, it is found that the steel cannot be easily withdrawn, the barrel will be drawn rearwardly7 by means of the handle 27 thus causing the plug 2 to extend into the rear end portion or the barrel toa greater extent than shown. The rear end of the hammer will now strike the inner end of the plug and tend to drive the plug rearwardly. Since the side bars l2 are connected with this plug, they will be moved rearwardly with the plug and a blow will be delivered to the hood to cause the hook to strike the shoulder 35 and cause the `drill to be extracted from the hole. By providing the springs 24 cushions are provided which serve to take up the torce of the blow received when the hammer strikes the inner end of the plug and breakage of the more delicate parts of the gun prevented. `When the valve 78 is moved from the open position shown in 2O to a closed position, air entering the expansion chamber to the rear of the piston may pass through the opening of the yhammer through which the water pipe 87 passes an-d through the drill steel to thoroughly clean the drill steel and hole which has been drilled in the rock.

t will thus be seen that there has been provided an air drill which will be very etlicient in operation and in which the drill steel may be caused to rotate in a step-bystep movement in either a left-hand or a right-hand direction. It will be further Y noted that there has been provided very etlicient pawls and adjusting means for these pawls and al-so that there has been provided an'improved type of hammer and ratchet sleeve actuated by the hammer. It will be further noted that there has been provided improved valve mechanism for controlling assaofe or' air into and out of the ex ansion chamber.

I claim l. An air drill comprising a barrel including an expansion chamber, a' hammer includ' with the barrel to slidably mount the barrel and prevent rotation thereof, land `aV handle element Carried bythe barrel tor sliding the barrel longitudinally and lcontrol the extent to which'the plug extends into the barrel, the hammer having striking engagement with the plug when the barrel is drawn rearwardly and having striking engagement with a drill steel when the bar rel is moved forwardly.

2. An air drill comprising a' barrel having an expansion chamber provided with valve controlled inlet and exhaust ports, a sleeve extending into the forward end oic the barrel and forming a forward head 'for said chamber, a plug fitting, into the rear end or the barrel and forming a rear head Jfor said chamber, a hammer slidable in said sleeve' and having its inner end portion extending into the expansion chamber and enlarged to form a piston, drill steel holding means including a chuck and a hood for the chuck, side bars carried by the plug, hood and forward end portion of said sleeve and engaging said barrel to mount the barrel for longitudinal sliding movement and prevent rotary movement of the barrel` the barrel being normally in position to prevent striking of the plug by the piston when moving rearwardly and movable rearwardly to pro.- ject the plug inwardly into position 'for striking by the piston, and drill steel engaging means carried by the hood 'for holding a drill steel in the ,chuck 3. An air drill comprising a barrel,"a sleeve extending into the forward end of the barrel, a plug fitting into the rear end of the barrel, the portion of the barrel between the plug and sleeve receiving portions forming an expansion chamber and having air inlet and outlet ports adjacent its ends, a hammer slidably litting in the sleeve and having its inner end portion positioned inA the expansion chamber and enlarged to provide a piston, a valve housing carried by said barrel land communicating with the expansion chamber through said ports, valve means in the housing for Controlling passage of air through said ports, drill steel carrier mechanism including a hood carried by the forward end portion of said sleeve, side bars carried by the hood, sleeve and plug and engaging the barrel to permit sliding movement thereof and hold the barrel against rotation, and handle means carried by said barrel whereby the barrel may be moved longitudinally to project the plug ,inwardly into position for striking by the hammer.

4. The structure of claim 3 having the plug and sleeve firmly held upon the side bars and the hood slidable upon the forwardv end portions of the side bars, and means for retaining the hood upon the rods and limiting sliding movement of the hood and bars relative to each other.

The structure of claim 3 having the plug and sleeve firmly held upon the side bars and the hood slidable upon the forward end portions of the side bars, fasteners carried by the forward ends of said bars, and cushioning means between the hood and fasteners.

6. The structure of claim 3 having the plug and sleeve firmly held upon the side bars and the hood slidable upon the forward end portions of the side bars, fasteners carried by the forward ends of said bars, and cushioning springs about the bars between the hood and fasteners to take up shocks received when the hammer strikes the plug forming the head for the rear end of the expansion chamber.

7. The structure of claim 3 having the barrel provided with sets of side arms extending above and between the side bars, the handle for the barrel being provided with arms having heads for engaging the upper side arms, and clamps carried by the heads for engaging the lower side arms and clamping the side arms to hold the handle in place.

S. The structure of claim 3 having the barrel provided with sets of side arms extending above and between the side bars, the handle for the barrel being provided with arms having heads for engaging the upper side arms, and clamps carried by the heads for engaging the lower side arms and clamping the side arms to hold the handle in place, the heads of the arms of Said handle being provided with lugs fitting into seats formed in the upper side arms and said heads having depending perforated side portions forming bearings, the clamps having feet extending beneath the lower side armsand stems extending through the bearings and having fasteners upon their upper end portions.

9. An air drill comprising a barrel including an expansion chamber, a hammer slid-` able in the barrel and having a piston forming portion positioned in the expansion chamber of the barrel, valve controlled means for permitting air to enter and leave the expansion chamber and impart movement to the hammer, a `sleeve extending into the forward end portion of the barrel y about the hammer and forming a head for the forward end of the expansion chamber, a plug in the rear end portion of the barrel forming a rear head for the expansion chamber, a hood fitting upon the forward end portion of said sleeve, a drill steel carrying chuck within the hood, means actuated by the hammer for imparting rotary movement to said chuck, side bars carried by the plug, sleeve and hood and guiding sliding movement of the barrel and holding the barrel against rotary movement, a handle carried by said barrel, the barrel when moved rearwardly by vsaid handle projecting the plug inwardly beyond the normal extent for engagement by the rear end of the hammer, and means carried by said hood for engaging a drill steel and drawing the steel rearwardly when the plug is struck by the hammer.

10. The structure of claim 2 having the hood provided with a reduced forward portion having its side portions provided with diagonally extending grooves open at their rear ends and closed at their lforward ends, the drill steel engaging device beingY in the form of a hook having arms extending rearwardly upon opposite sides of the hood and provided with side pins fitting into the grooves to pivotally mount the hook, end pins extending from the arms 'and springs about the end pins engaging Vthe hood at the rear end of the reduced forward portion to frictionally hold the hook against pivotal movement.

In testimony whereof I have hereunto set my hand. v

GINES PEREZ GOMEZ.- 

